PHYSICAL OCEANOGEAPHY OF THE GULP OF MAINE 



759 



Channel on the 4th (station 10281, 31.8 per mille from surface to bottom), is an 

 interesting illustration of the local differences to be expected at neighboring stations 

 in these tide-swept waters. 



Near Mount Desert, too, observations taken at three stations on June 11 to 

 14, 1915 (stations 10284, 10285, and 10286), show much less difference between sui"- 

 face and bottom than on May 10 and 11 (stations 10274 and 10275), the surface 

 having salted by about 0.5 per mille in the interval, but the bottom by not more 



Fig. 131. 



-Vertical distribution of salinity in the southeastern part of the basin of the gulf. A, March, 1920 (station 20064); 

 B, April, 1920 (station 20112); C, June, 1915 (station 10298); D, July, 1914 (station 10225) 



than 0.2 per mUle. Off the mouth of Penobscot Bay, however, near the 100-meter 

 contour, no appreciable change took place in the salinity at any depth from May 

 12, 1915 (station 10276), to June 14 (station 10287). 



In Massachusetts Bay, which receives very little river water from its own coast 

 line, the Fish Hawk cruises of 1925 showed an increase in salinity, surface to bottom, 

 between the 20th of May (cruise 13) and the middle of June, averaging about 0.7 per 

 mille for all the stations and levels combined, with a maximum change of 1.3 per 



